MITOCHONDRIAL-DNA SEQUENCE VARIATION IN THE EASTERN HOUSE MOUSE, MUS MUSCULUS - COMPARISON WITH OTHER HOUSE MICE AND REPORT OF A 75-BP TANDEM REPEAT

The control region and flanking tRNAs were sequenced from 139 Mus musc ulus mitochondrial DNAs (mtDNAs) from mice collected at 44 localities extending from Germany to Japan. Among the 36 types of M. musculus mtD NA resolved, five have an added 75-bp direct repeat; the two copies wi thin an individual differ by two to four base substitutions. Among 90 M. domesticus mtDNAs sequenced, 12 new types were found; 96 M. domesti cus types have now been identified by sequencing this segment. Represe ntative mtDNAs from M. castaneus, M. macedonicus, M. spicilegus and M. spretus were also sequenced. A parsimony tree for the M musculus mtDN As is about half as deep as the tree for the M. domesticus mtDNAs, whi ch is consistent with the idea that M. musculus is genetically less di verse and younger than M. domesticus. The patterns of variation as a f unction of position are similar but not identical in M. musculus and M . domesticus mtDNAs. M. castaneus and M. musculus mtDNAs are allied, a t a tree depth about three times as great as the start of intra-M. mus culus divergence. The coalescence of the M. musculus and M. castaneus mtDNAs is about half as deep as their coalescence with the M. domestic us mtDNA lineages. The mtDNAs of the aboriginal M. macedonicus and M. spicilegus are each other's closest relatives, at a tree depth greater than the deepest intracommensal node. The mtDNA results support the v iew that the aboriginal M. spretus is the sister group of the other fi ve species.